Tuesday, May 29, 2012

Nat'l Academies Pre-print Report on Discipline-Based Education Research

This 270 page "synthesis study" collects the literature and assesses research on approaches to undergraduate science education.  I haven't read the report, just skimmed the 19-page Executive Summary. 

Most reports by the National Academies can be read online for free, including this one.  From the Exec. Summ.:
DBER scholars have devoted considerable attention to effective instructional strategies and to students’ conceptual understanding, problem solving, and use of representations. Key findings from DBER are consistent with cognitive science research and studies in K-12 education.

To gain expertise in science and engineering, students must learn the knowledge, techniques, and standards of each field. However, across the disciplines, the committee found that students have incorrect understandings about fundamental concepts, particularly those that involve very large or very small temporal and spatial scales. Moreover, as novices in a domain, students are challenged by important aspects of the domain that can seem easy or obvious to experts, such as problem solving and understanding domain-specific representations like graphs,
models, and simulations. These challenges pose serious impediments to learning.

DBER clearly shows that research-based instructional strategies are more effective than traditional lecture in improving conceptual knowledge and attitudes about learning. Effective instruction involves a range of approaches, including making lectures more interactive, having students work in groups, and incorporating authentic problems and activities.

To enhance DBER’s contributions to the understanding of undergraduate science and engineering education, the committee recommended:
  • Research that explores similarities and differences among different student
    populations.
  • Longitudinal studies—including studies of the K-12/undergraduate transition— to better understand the acquisition of important concepts and factors influencing retention.
  • More studies that measure outcomes other than test scores and course performance, and better instruments to measure these outcomes.
  •  Interdisciplinary studies of cross-cutting concepts and cognitive processes.

Tuesday, May 01, 2012

Inexpensive ethylene sensor reported

Megan Scudellari reported in The Scientist on April 30 in "Sensor Measures Produce Ripeness," on a 25 cent ethylene sensor developed by chemists at MIT that could help grocers and shippers gauge the ripeness of fruits and vegetables.
The sensor, described April 19 in the journal Angewandte Chemie [International Edition], is made of an array of tens of thousands of carbon nanotubes modified with copper atoms, which bind ethylene and allow scientists to measure the amount of gas present. The researchers successfully tested their sensors on bananas, avocados, apples, pears, and oranges, accurately determining their ripeness.
The inexpensive devices could someday be attached to cardboard boxes of produce and scanned with a handheld device to reveal the contents’ ripeness, said [MIT's Timothy] Swager. Then, grocers would know when to put items on sale before they get too ripe.
If you are a member of the University of Massachusetts Amherst community, you can read the Angewandte Chemie article using the library's subscription.
  • On campus, use this link.  
  • Off campus, use this link - you will need to authenticate yourself using an OIT username and password, and navigate to the full text of the article.

As a past student of post-harvest physiology, I suspect this device could be a real boon to the industry and the consumer, and result in much less wasted produce.